There are at least three different cultivars of crabapple in the Park, but since members of the genus Malus hybridize fairly freely, I am going to lump all the cultivars together for this page. See Wikipedia entry here for the genus.
Centurion crab in the east triangle in April, looking northeast.
The genus Malus contains 30-55 species, all of which are "apples." One of those cultivated species, Malus domesticus, with its 7,500 known varieties, is the commercial apple. This is analogous to the origins of our pet dogs, Canis lupus familiaris, and all its separate breeds engineered by humans, from the wild wolf, Canis lupus.
Most crabapples have a bitter taste, due to the chemical malic acid. This chemical name is derived from the Latin word malum, meaning evil. This has nothing to do with the Bible, as the forbidden fruit in the story of Adam and Eve is never specified. The Latin word for apple, malum, is pronounced with a long "a" and derives from the Greek word for melon.
The leaves are serrated like the cherry tree, and the small crabapples can look like cherries in July. The bark distinguishes the two, since cherry has smooth purplish bark with lenticels, and crabs have thich bark with longitudinal furrows.
Many apple experts will define an apple as having a diameter of at least two inches. Anything less than that diameter is a crabapple.
Nicely shaped gold harvest crabapple in the southwest triangle in April, looking east
Brandywine crabapple already burdened with fruit in the southeast triangle, in July, facing east
Centurion crabapple in the northeast triangle in April, facing north
There are at least three different species in the Park that can be confused with each other, since they all have profuse flowers in the spring; two have small cherry-like fruit; and they all have oblate green leaves with serrated edges. They can be easily distinguished by the bark.
Crabapple with cherry-like fruit and serrated leaves in July. The bark is thick and furrowed longitudinally when mature.
Thornless hawthorn with haws and leaves with serrated edges in July. The bark is thin and peeling giving an army desert camouflage appearance.
The ornamental cherries in the Park have serrated leaves and distinctive smooth purple bark with lenticels (horizontal pores). They do not bear any fruit.